Among schizophrenics, a reduction in verbal productivity is stable and is associated with poor prognosis and increased severity of disturbance. The goal of the proposed project is to utilize knowledge and methodological approaches developed in the related fields of psycholinguistics, neuropsychology, neurolinguistics, and linguistic aphasiology to test hypotheses concerning the etiology of alogia. The specific aims of the proposed project are to examine whether alogia is associated with: (1) frontal lobe dysfunction; (2) a word finding deficit similar to that seen in anomic aphasia; (3) a deficit in verbal planning ability similar to that seen in dynamic aphasia; and (4) an information processing disturbance. In addition, the proposed project would examine whether the factors that are associated with alogia among schizophrenics are also associated with alogia among individuals with depressive disturbances. One hundred hospitalized psychiatric patients (50 individuals with schizophrenia or schizoaffective disorder, and 50 individuals with depressive disturbances) will be audiotaped while they answer a series of open-ended questions. These interviews will be used to measure verbal productivity, syntactic complexity, response latencies, within-clause pauses, and between-clause pauses. Subjects will also complete a series of tests designed to measure the functioning of several different brain regions, word finding ability, verbal and non-verbal planning abilities, and information processing abilities. The proposed study will not only improve our understanding of alogia, it will also enhance our understanding of the neurological and cognitive disturbances that underlie the development and chronic course of schizophrenia.